Chapter 36. ECPG - Embedded SQL in C

Table of Contents

36.1. The Concept
36.2. Managing Database Connections
36.2.1. Connecting to the Database Server
36.2.2. Choosing a Connection
36.2.3. Closing a Connection
36.3. Running SQL Commands
36.3.1. Executing SQL Statements
36.3.2. Using Cursors
36.3.3. Managing Transactions
36.3.4. Prepared Statements
36.4. Using Host Variables
36.4.1. Overview
36.4.2. Declare Sections
36.4.3. Retrieving Query Results
36.4.4. Type Mapping
36.4.5. Handling Nonprimitive SQL Data Types
36.4.6. Indicators
36.5. Dynamic SQL
36.5.1. Executing Statements without a Result Set
36.5.2. Executing a Statement with Input Parameters
36.5.3. Executing a Statement with a Result Set
36.6. pgtypes Library
36.6.1. Character Strings
36.6.2. The numeric Type
36.6.3. The date Type
36.6.4. The timestamp Type
36.6.5. The interval Type
36.6.6. The decimal Type
36.6.7. errno Values of pgtypeslib
36.6.8. Special Constants of pgtypeslib
36.7. Using Descriptor Areas
36.7.1. Named SQL Descriptor Areas
36.7.2. SQLDA Descriptor Areas
36.8. Error Handling
36.8.1. Setting Callbacks
36.8.2. sqlca
36.9. Preprocessor Directives
36.9.1. Including Files
36.9.2. The define and undef Directives
36.9.3. ifdef, ifndef, else, elif, and endif Directives
36.10. Processing Embedded SQL Programs
36.11. Library Functions
36.12. Large Objects
36.13. C++ Applications
36.13.1. Scope for Host Variables
36.13.2. C++ Application Development with External C Module
36.14. Embedded SQL Commands
ALLOCATE DESCRIPTOR — allocate an SQL descriptor area
CONNECT — establish a database connection
DEALLOCATE DESCRIPTOR — deallocate an SQL descriptor area
DECLARE — define a cursor
DESCRIBE — obtain information about a prepared statement or result set
DISCONNECT — terminate a database connection
EXECUTE IMMEDIATE — dynamically prepare and execute a statement
GET DESCRIPTOR — get information from an SQL descriptor area
OPEN — open a dynamic cursor
PREPARE — prepare a statement for execution
SET AUTOCOMMIT — set the autocommit behavior of the current session
SET CONNECTION — select a database connection
SET DESCRIPTOR — set information in an SQL descriptor area
TYPE — define a new data type
VAR — define a variable
WHENEVER — specify the action to be taken when an SQL statement causes a specific class condition to be raised
36.15. Informix Compatibility Mode
36.15.1. Additional Types
36.15.2. Additional/Missing Embedded SQL Statements
36.15.3. Informix-compatible SQLDA Descriptor Areas
36.15.4. Additional Functions
36.15.5. Additional Constants
36.16. Oracle Compatibility Mode
36.17. Internals

This chapter describes the embedded SQL package for Postgres Pro. It was written by Linus Tolke () and Michael Meskes (). Originally it was written to work with C. It also works with C++, but it does not recognize all C++ constructs yet.

This documentation is quite incomplete. But since this interface is standardized, additional information can be found in many resources about SQL.